This invention relates to actuators for overrunning roller clutches of the type commonly employed between drive and driven members of vehicles having auxiliary driving axles. More particularly, the invention relates to actuators of the positive engagement type whereby frictional losses are eliminated during disengagement of the clutch or whenever the clutch is in its "free wheeling" mode.
Numerous prior art devices have been utilized which afford positive engagement and disengagement of roller clutches. However, even though such devices have been successful in avoiding friction losses and the inadvertent actuation potential associated with actuators of the non-positively engaging type, the latter positive engagement actuators tend to be plagued by an increased wear of parts and a jerkiness to vehicular operation as created by the abrupt nature of the engagement of such devices.
For example, U.S. Pat. No. 3,123,169 to R. C. Young et al discloses a roller clutch actuator of the positive engagement type. The cage member 44 therein includes serrations which engage mating serrations of a friction ring selectively engageable therewith. The result is a dog clutching action, which is associated with the aforenoted jerkiness and accelerated wear of parts. Although the system disclosed therein includes many positive virtues, a more desirable system would be one in which a less abrupt, hence more time-controlled actuation occurs, and one in which the resultant roller clutch engagement is positive, yet resilient.